/usr/lib/python3/dist-packages/rsa/pem.py is in python3-rsa 3.4.2-1.
This file is owned by root:root, with mode 0o644.
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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 | # -*- coding: utf-8 -*-
#
# Copyright 2011 Sybren A. Stüvel <sybren@stuvel.eu>
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# https://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
"""Functions that load and write PEM-encoded files."""
import base64
from rsa._compat import b, is_bytes
def _markers(pem_marker):
"""
Returns the start and end PEM markers
"""
if is_bytes(pem_marker):
pem_marker = pem_marker.decode('utf-8')
return (b('-----BEGIN %s-----' % pem_marker),
b('-----END %s-----' % pem_marker))
def load_pem(contents, pem_marker):
"""Loads a PEM file.
:param contents: the contents of the file to interpret
:param pem_marker: the marker of the PEM content, such as 'RSA PRIVATE KEY'
when your file has '-----BEGIN RSA PRIVATE KEY-----' and
'-----END RSA PRIVATE KEY-----' markers.
:return: the base64-decoded content between the start and end markers.
@raise ValueError: when the content is invalid, for example when the start
marker cannot be found.
"""
# We want bytes, not text. If it's text, it can be converted to ASCII bytes.
if not is_bytes(contents):
contents = contents.encode('ascii')
(pem_start, pem_end) = _markers(pem_marker)
pem_lines = []
in_pem_part = False
for line in contents.splitlines():
line = line.strip()
# Skip empty lines
if not line:
continue
# Handle start marker
if line == pem_start:
if in_pem_part:
raise ValueError('Seen start marker "%s" twice' % pem_start)
in_pem_part = True
continue
# Skip stuff before first marker
if not in_pem_part:
continue
# Handle end marker
if in_pem_part and line == pem_end:
in_pem_part = False
break
# Load fields
if b(':') in line:
continue
pem_lines.append(line)
# Do some sanity checks
if not pem_lines:
raise ValueError('No PEM start marker "%s" found' % pem_start)
if in_pem_part:
raise ValueError('No PEM end marker "%s" found' % pem_end)
# Base64-decode the contents
pem = b('').join(pem_lines)
return base64.standard_b64decode(pem)
def save_pem(contents, pem_marker):
"""Saves a PEM file.
:param contents: the contents to encode in PEM format
:param pem_marker: the marker of the PEM content, such as 'RSA PRIVATE KEY'
when your file has '-----BEGIN RSA PRIVATE KEY-----' and
'-----END RSA PRIVATE KEY-----' markers.
:return: the base64-encoded content between the start and end markers.
"""
(pem_start, pem_end) = _markers(pem_marker)
b64 = base64.standard_b64encode(contents).replace(b('\n'), b(''))
pem_lines = [pem_start]
for block_start in range(0, len(b64), 64):
block = b64[block_start:block_start + 64]
pem_lines.append(block)
pem_lines.append(pem_end)
pem_lines.append(b(''))
return b('\n').join(pem_lines)
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